電大機電控制工程基礎作業(yè)4

1、機電控制工程基礎作業(yè)4單項選擇題 第1題 pid控制器的傳遞函數(shù)形式是（）。 a、5+3s b、5+3/s c、5+3s+3/s d、5+1/s+1 答案：c 第2題 拉氏變換將時間函數(shù)轉換為（）。 a、正弦函數(shù) b、單位階躍函數(shù) c、單位脈沖函數(shù) d、復變函數(shù) 答案：d 第3題 線性定常系統(tǒng)的傳遞函數(shù)，是在零初始條件下的（）。 a、系統(tǒng)輸出信號與輸入信號之比 b、信號輸入信號與輸出信號之比 c、系統(tǒng)輸入信號的拉氏變換與輸出信號的拉氏變換之比 d、系統(tǒng)輸出信號的拉氏變換與輸入信號的拉氏變換之比 答案：d 第4題 pid控制器中，積分控制的作用是（）。 a、客服對象的延遲和慣性 b、能使控制過程

2、為無差控制 c、減少控制過程的動態(tài)偏差 d、使過程較快速的達到穩(wěn)定 答案：c 第5題 當二階系統(tǒng)的根分布在右半根平面時，系統(tǒng)的阻尼比為（）。 a、阻尼比小于0 b、阻尼比等于0 c、阻尼比在0和1之間 d、阻尼比大于1 答案：d 第6題 時域分析法中最常用的典型輸入信號是（）。 a、脈沖函數(shù) b、斜坡函數(shù) c、階躍信號 d、正弦函數(shù) 答案：c 第7題 傳遞函數(shù)反映了系統(tǒng)的動態(tài)性能，它與下列哪些因素有關？（） a、輸入信號 b、初始條件 c、系統(tǒng)的結構參數(shù) d、輸入信號和初始條件 答案：c 第8題 采用系統(tǒng)的輸入、輸出微分方程對系統(tǒng)進行數(shù)學描述是（）。 a、系統(tǒng)各變量的動態(tài)描述 b、系統(tǒng)的外部描

3、述 c、系統(tǒng)的內(nèi)部描述 d、系統(tǒng)的內(nèi)部和外部描述 答案：a 第9題 根據(jù)給定值信號的特點分類，控制系統(tǒng)可以分為（）。 a、恒值控制系統(tǒng)、隨動控制系統(tǒng)和程序控制系統(tǒng) b、反饋控制系統(tǒng)、前饋控制系統(tǒng)和復合控制系統(tǒng) c、最優(yōu)控制系統(tǒng)和模糊控制系統(tǒng) d、連續(xù)控制系統(tǒng)和離散控制系統(tǒng) 答案：a 第10題 系統(tǒng)特征方程式的所有根均在根平面的左半部是系統(tǒng)穩(wěn)定的( )。 a、充分條件 b、必要條件 c、充分必要條件 d、以上都不是 答案：a 第11題 脈沖函數(shù)拉氏變換為( )。 a、0 b、無窮大 c、常數(shù) d、變量 答案：b 第12題 理想微分環(huán)節(jié)對數(shù)幅頻特性曲線是一條斜率為( )。 a、20db/dec,通

4、過=1點的直線 b、負20db/dec,通過=1點的直線 c、負20db/dec,通過=0點的直線 d、20db/dec,通過=0點的直線 答案：a 第13題 線性系統(tǒng)和非線性系統(tǒng)的根本區(qū)別在于( )。 a、線性系統(tǒng)有外加輸入，非線性系統(tǒng)無外加輸入 b、線性系統(tǒng)無外加輸入，非線性系統(tǒng)有外加輸入 c、線性系統(tǒng)滿足迭加原理，非線性系統(tǒng)不滿足迭加原理 d、線性系統(tǒng)不滿足迭加原理，非線性系統(tǒng)滿足迭加原理 答案：c 第14題 根據(jù)輸入量變化的規(guī)律分類，控制系統(tǒng)可分為( )。 a、恒值控制系統(tǒng)、隨動控制系統(tǒng)和程序控制系統(tǒng) b、反饋控制系統(tǒng)、前饋控制系統(tǒng)和前饋反饋復合控制系統(tǒng) c、最優(yōu)控制系統(tǒng)和模糊控制系統(tǒng)

5、 d、連續(xù)控制系統(tǒng)和離散控制系統(tǒng) 答案：a 第15題 設控制系統(tǒng)的開環(huán)傳遞函數(shù)為g(s)=10/（s+1)(s+2) ，該系統(tǒng)為( )。 a、0型系統(tǒng) b、i型系統(tǒng) c、ii型系統(tǒng) d、iii型系統(tǒng) 答案：b 第16題 微分環(huán)節(jié)的頻率特性相位移()=( )。 a、90 b、負90 c、0 d、負180 答案：a 第17題 積分環(huán)節(jié)的頻率特性相位移()=( )。 a、90 b、負90 c、0 d、負180 答案：b 第18題 有一線性系統(tǒng)，其輸入分別為u1(t)和u2(t)時，輸出分別為y1(t)和y2(t)。當輸入為a1u1(t)+a2u2(t)時(a1,a2為常數(shù))，輸出應為( )。 a、a

6、1y1(t)+y2(t) b、a1y1(t)+a2y2(t) c、a1y1(t)-a2y2(t) d、y1(t)+a2y2(t) 答案：b 待添加的隱藏文字內(nèi)容2第19題 i型系統(tǒng)開環(huán)對數(shù)幅頻漸近特性的低頻段斜率為( )。 a、負40(db/dec) b、負20(db/dec) c、0(db/dec) d、20(db/dec) 答案：b 第20題 比例環(huán)節(jié)的頻率特性相位移()=( )。 a、90 b、負90 c、0 d、180 答案：c if we dont do that it will go on and go on. we have to stop it; we need the cou

7、rage to do it.his comments came hours after fifa vice-president jeffrey webb - also in london for the fas celebrations - said he wanted to meet ivory coast international toure to discuss his complaint.cska general director roman babaev says the matter has been exaggerated by the ivorian and the brit

8、ish media.blatter, 77, said: it has been decided by the fifa congress that it is a nonsense for racism to be dealt with with fines. you can always find money from somebody to pay them.it is a nonsense to have matches played without spectators because it is against the spirit of football and against

9、the visiting team. it is all nonsense.we can do something better to fight racism and discrimination.this is one of the villains we have today in our game. but it is only with harsh sanctions that racism and discrimination can be washed out of football.the (lack of) air up there watch mcayman islands

10、-based webb, the head of fifas anti-racism taskforce, is in london for the football associations 150th anniversary celebrations and will attend citys premier league match at chelsea on sunday.i am going to be at the match tomorrow and i have asked to meet yaya toure, he told bbc sport.for me its abo

11、ut how he felt and i would like to speak to him first to find out what his experience was.uefa hasopened disciplinary proceedings against cskafor the racist behaviour of their fans duringcitys 2-1 win.michel platini, president of european footballs governing body, has also ordered an immediate inves

12、tigation into the referees actions.cska said they were surprised and disappointed by toures complaint. in a statement the russian side added: we found no racist insults from fans of cska.baumgartner the disappointing news: mission aborted.the supersonic descent could happen as early as sunda.the wea

13、ther plays an important role in this mission. starting at the ground, conditions have to be very calm - winds less than 2 mph, with no precipitation or humidity and limited cloud cover. the balloon, with capsule attached, will move through the lower level of the atmosphere (the troposphere) where ou

14、r day-to-day weather lives. it will climb higher than the tip of mount everest (5.5 miles/8.85 kilometers), drifting even higher than the cruising altitude of commercial airliners (5.6 miles/9.17 kilometers) and into the stratosphere. as he crosses the boundary layer (called the tropopause),e can ex

15、pect a lot of turbulence.the balloon will slowly drift to the edge of space at 120,000 feet ( then, i would assume, he will slowly step out onto something resembling an olympic diving platform.below, the earth becomes the concrete bottom of a swimming pool that he wants to land on, but not too hard.

16、 still, hell be traveling fast, so despite the distance, it will not be like diving into the deep end of a pool. it will be like he is diving into the shallow end.skydiver preps for the big jumpwhen he jumps, he is expected to reach the speed of sound - 690 mph (1,110 kph) - in less than 40 seconds.

17、 like hitting the top of the water, he will begin to slow as he approaches the more dense air closer to earth. but this will not be enough to stop him completely.if he goes too fast or spins out of control, he has a stabilization parachute that can be deployed to slow him down. his team hopes its not needed. instead, he plans to deploy his 270-square-foot (25-square-meter) main chute at an altitude of around 5,000 feet (1,524 meters).in order to deploy this chute successfully, he will have to slow to 172 mph (277 kph). he will have a reserve parachute that wi